A few points:
Sydeals says you can buy Cholov Yisrael virtually anywhere in America. Definitely not true. It’s not available anyplace that’s far from a major center of frumkeit. Try getting CY in North Dakota (other than by going to a dairy farm and watching the milking yourself). This is a problem for Chabad shluchim.
ZD is correct in saying that it’s simply not practical for a dairy farmer to mix pig’s milk into his cow’s milk. I found an article that says it’s very difficult to milk a pig anyway. In the U.S., there’s no economic incentive to pass off the milk of a beheimah t’mayah as cow’s milk.